Re: Billions of records? - Mailing list pgsql-general

From Shridhar Daithankar
Subject Re: Billions of records?
Date
Msg-id 200307152023.00391.shridhar_daithankar@nospam.persistent.co.in
Whole thread Raw
In response to Billions of records?  (John Bercik <bercikj@musc.edu>)
List pgsql-general
On Tuesday 15 July 2003 20:01, John Bercik wrote:
> Thanks for the reply.  So given my conditions, how many records can PG
> hold?  I got the 16TB from the limitations page but I don't see how to
> calculate how many records I can hold.

OK. Let's calculate. You have 50 fields of 20 char each. So each field would
go for 24 bytes at least assuming a 4 byte integer for length.

So a tuple size is 50*24+28=1228 bytes. So in a page of 8KB, you would get 6
tuples.

In 16TB you can accomodate, 2GB pages. So you can accomodate around 12 billion
tuples for your table schema.

If you get true char types, that would accomodate  7 tuples per page. So you
could get around 14 billion tuples in there.

HTH

BTW How much data you actually have?

 Shridhar


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